Manufacture of sodium permanganate



I' lo Brewing.

To all whom it may concern:

Be it {HOWE that l, DANIEL TYL. ject ot the limo; oi" Great Brita I inElto ldmi-oir'fees England, have ii ed certain new and useful liuprovemei i the Manuiatture oi? Sodium Perinauganate, of which the following; isa specification.

it. known process or" making sodium permau anate consists in firstpreparing loarium manganate, then converting this into the permanganate,then decomposing the barium permanganate with sodium carbon ate orsulfate and finally crystalliziug the solution of sodium permanga. atethus do tained.

There is dithculty in satisfactorily couverting the barium manganateinto the permanganate; the desired ehang. is expressed by the equation:

hut the conversion is not complete.

Another dilliculty in the process is the iso lation of the sodium 13'-ianqa-note Toy crystallization because it separates in the form of asludge of line crystals which can only with dilliculty be separated fromthe mother liquor. Complete evaporation is also impracticable ecause ofthe danger of decomposing" some of the product by over-heating.

My inven u consists in a process wherein these dilliculties are to aextent elimiuated.

A substantially complete conversion or. the barium manganate intopermanganate is brought about by adding the sulfuric. acid to thesuspension of the inanganate in water extremely slowly at first, withthe effect. l presume, that the first pcrmano'anate formed is decomposedhy the sulfuric a id ii era;- lf 3 1 imangauic acid the unchanged bariummuu c 'anate is decomposed by the permanganic acid. .ilnother and.better method of applying this principle is to add first to the bariummaao'ai ate a so lution of harium permai "111i1l0 previously preparedand ti on sulturi acid gradually. so that the free acid actually presentin the liquor is perms-organic and not sulfuric aid. l i hen thereaction is complete any slight residual acidity may he neutralized. bybarium hydrate.

The barium i errnanganate solution is then converted into sodiumpermanganate solution in known manner and after filtration tlon meltsi1. lt is. .i necessary to evaporate the soutioiuntih on. coolincomplete". ll hen this degree of concen een attained the liquor is runinto "rats or molds in which 0 .1

to a dry crystalline mass 'WlllCll a composititui approximat ing; toNalurulh 3Jfi t, hut it may contain less Water than at re )resented bythis for mole.

The following examples illustrate the inventi n:

Example 1: 1.00 kilos of barium manganuts are suspended in 1000 to 15%liters of Wa'er at ordinal-3.7 temperati and 5 kilos of sulfuric acid of50 per cent. strei '"h are added at the rate of 100%? c. c. oer minute,the mix ure being thoroughly stirred While the addition pro ::eeds. Aler onethird of the acid has heen added in this manner the rest may heintroduced more rapidly. When the Whole of the acid has been added, thestirring is continued for halt-an hour and then the liquor, it arid, isneutralized with barium hydrate. A. solution or" sodium sulfate or 20per cent. stren "h is now introduces While stirring is maintiiined untilthe liquor contains no barium in so lution. After a few minutes thesolid matter is separated from the liquid in any known manner and thesolution of sodium permanganate thus obtained is GVSDOIEFEEd 1. 1 1 o LV, I at aoout 1.00 C. until a sample solidlnes on cooling. The Whole isthen allowed to cool and the mass broken up or ground.

When a high degree of purity of the fin ished product not essential andthe parent 1 i.

:arium mang'anate has been made by addharium hydrate to sodiummanganate, 1'18 arium mangauate may he left suspended in the solution ofsodium hydronid formed by the reaction and this suspension treated withsulfuric acid in suitably chan ed proportion, first to neutralize thealkali and then to react in the manner described in this example. Thestep of adding sodium sulfate may then be unnecessary, as will hereadily understood by the chemist.

Example 2 lOOlzilos of barium manganate 5e ductin the conversion of theletter are suspended in 1.000 liters of Water at ordinary temperatureeohteiuiiie' kilos of barium permanganate and "the addition of sulfuricacid conducted as described in EX- eniple 1 except that the rate ofaddition may he 3 to 4 times as rapid, thus saving time in the process.The rest of the operation is similar to that described in Example 1.

Having thus described the nature of the said invention and the bestmeans l know of can" 'in the same into Tactical effect I. b 9

claim 1 .1. in the manufacture I' sodium mangenate from bariummenganete,

per-- coninto 7 1 seems nate ultimately obtained until it solid' 05.1cooling.

2. In the manufacture of sodium per-iii an gamete from barium meugaheteas defined in claim 1, adding sulfuric acid to a suspension of bariuminangmete in the presence of barium permanganate.

in testimony whereof name to this specification;

DANIEL TYRE.

I have. signed my

